Linux COL
Linux COL
Linux fundamentals
Question 1: Unix systems are characterized by a modular design that is sometimes called the, what?
Unix philosophy
Question 2: The Unix operating system should provide a set of simple tools known as, what?
Core utils
Question 3: What is the name of the GNU kernel?
Linux
Question 1: The POSIX shell is the same as which shell?
Bourne Shell
Question 2: What is the default shell on GNU/Linux?
BASH
Question 3: True or False: The CLI, terminal, and shell are just different names for the same thing.
False
Question 1: What is the root of the filesystem?
/
Question 2: What is the name of the user that lives in kernel land?
root
Question 3: What is the home directory of the root user?
/root
Question 4: What is the administrator on a Linux system?
Sudo “super user do” (anyone able to run “sudo”)
Question 1: What is a device driver?
Translation layer between OS to User
Question 2: What are the two types of device drivers?
User mode and kernel mode
Question 1: Where are log files kept?
/var/log
Question 2: Where are system configuration files located?
/etc
Question 3: True or False - The /usr/bin directory contains required binaries.
false
Question 1: What is the ~ short for?
Home directory of the user
Question 2: What is a single dot short for?
Current working directory
Question 3: Where does the absolute path for a file or directory start?
“ / “
Linux Internals
Question 1: What is the fundamental interface between an application and the Linux kernel?
System calls
Question 2: What is the command to pull up system calls by number on a Linux machine?
Ausyscall –dump
Question 3: What is the name of the C library on GNU/Linux called?
Glibc
Question 1: What is the file type for executable files in Unix/Linux?
elf
Question 2: What is the GNU C library called?
glibc
Question 3: What does the mmap system call do?
Map data to memory
Question 1: True or False: A reboot is required when one installs a LKM?
false
Question 2: What is the command to list loaded kernel modules?
lsmod
Question 3: What does the .ko file extension stand for?
Kernel object
Question 1: What are some of the common arguments used with the ps command?
Ef elf and aux
Question 2: What is a type of process that runs in the background without any human interaction?
Daemon
Question 1: What are the three types of login shells?
bash , gui, ssh
Question 2: What shell actively reads commands from user input?
Interactive shell
Question 1: What argument is used with the "su" command to open a BASH login?
- , -l, –login
Question 2: What argument opens a BASH login with the "bash" command?
Bash -l , bash –login
Question 1: What is the restricted BASH shell called?
rbash
Question 1: What command is used to print environmental variables?
env , printenv
Question 2: What environmental variable is checked when we execute a command in the shell?
The path
Question 1: SSH's most notable applications are what?
Remote login, command line execution
Question 2: Name one file transfer protocol based on SSH.
scp(secure copy) , sftp(secure file transfer protocol), rsync
Authentication and Authorization
What is an administrator account?
Account to run commands as a root user
What type of account do users like Apache have?
Service accounts
What type of accounts belong to users like sys or a daemon?
System accounts
What file contains user information?
/etc/passwd
Where are user password hashes stored?
/etc/shadow
Where are local user configurations stored?
~/.bashrc
What restricts the rights and access of a user to the minimal amount required to perform their role?
Principle of least privilege
What element of user management says administrators of a system should not share accounts?
Individual accounts
What are some of the basics of password management?
Require the password to be changed periodically, do not allow the reuse of old passwords, require that they be of some level of complexity
Logs Auditing Software
SystemV has run levels, what did SystemD migrate too?
targets
In SystemV Linux what is the centralized configuration File?
/etc/inittab
What is rsyslog?
Improved faster syslog
What command is used for querying systemd for logs, and has taken a good part of the old syslog?
journalctl
What command is used to edit the crontab?
Crontab -e
What is each field of the crontab?
Minute, hour, day of the month, month of the year, day of week, script or command
What is the Debian package manager called?
apt
A package is a container for ?
Metadata
Net services admin
Question 1: What command is used to check network connectivity?
Ping
Question 2: What command is used to display the routing table?
route
Question 1: What information do you need to configure an IP address?
Ip address, network mask, default gateway
Question 2: What are three command line tools used to interact with Networkd?
Networkctl nmtui, nmcli
Question 3: The d after a process name ie Networkd stands for what?
daemon
Question 1: Samba’s functionality comes from what two protocols?
SMB & CIFS
Question 2: What does Samba do?
Allows file and print sharing across OSs
Question 1: Samba security modes are set in which file?
SMB.comp
Question 2: What are the two security modes in Samba?
User and shared
Question 1: What protocol does LDAP sit on top of?
tcp/ip
Question 2: What are two common implementations of LDAP?
Active directory(AD) for windows and openLDAP for linux
Question 1: The majority of Apache servers run on what system?
linux
Question 2: Where is the index.html file located?
/var/www/html
Question 1: What are the symbols used to denote request and response headers?
> “request” & < “response”
Question 2: What code means everything worked correctly?
200 OK